If you and your Dad want to go for a drive, and camp, head down past Burns, then go to French Glen, past French Glen to Catlow valley, and out toward the Alvord desert. In the areas around Catlow valley, and the Alvord desert you can camp, and there is tons of BLM land where you can shoot. There are also some free hot springs outside of Fields.
If you want to stay somewhere, you can stay at the French Glen Inn, across the road from them is the Steens mountain resort. The steens mountain resort is actually a collection of decent mobile homes where you can sleep, cook, and relax. A really nice way to do things is to reserve your meals at the French Glen inn, get a lunch to go, they just sleep at the Steens mountain resort. There is also a little hotel in Fields that has about 10 rooms.
Both these places are a full 8-10 hours drive from portland. It takes about 6 hours to get to Burns, and another hour or two to get to the French Glen inn. Look it up on the internet as it is a famous stage coach stop. If you have never been in this area, you and your Dad can have a great time. There is also fishing at Mann Lake, and other places.
This is the far S.E. corner of the state, and is extremely remote. Don't think about going there with tires that aren't tough. I had good tires, and blew out both rear tires once.. It took a full half day before some kind soul took me from where I was into Burns, and back to my vehicle. That is the sort of kindness that isn't soon forgotten. The people down there are pure gold as far as I am concerned.
'Ya gotta ask yourself, "How many people from the Portland area would take a complete stranger and his two blown out tires two hours to a repair shop, wait with you while your tires get fixed, then take you two hours back to your vehicle, help you replace both tires, and do it all with a smile?"
The distances you can shoot down there are easliy 2000 yards or more.. Even a 416 Barret would run out of room down there.